Shape Control Method For Nanoparticles For Making Better And New Catalysts

Abstract

A method for shape controlled synthesis of colloidal metal nanoparticles includes providing a solution of 8x10-5 M K₂ PtCl₄ and water in a reaction vessel and maintaining the vessel at a constant temperature of approximately 25°C. 0.1 M sodium polyacrylate is then added to the solution. Thereafter, argon gas is bubbled through the solution for approximately 20 minutes, and then hydrogen gas is bubbled through the solution for approximately 5 minutes to saturate the solution and so that platinum ions in the solution are reduced. The reaction vessel is sealed and the solution is allowed to stand for approximately 12 hours, whereby platinum colloidal nanoparticles possessing a particular shape distribution and size distribution are formed. The shape and size distributions of produced nanoparticles can be manipulated by changing the ratio of the concentration of sodium polyacrylate to platinum ions in a subsequently formed solution while maintaining all other variables constant.